Rube Goldberg machines are deliberately complex contraptions consisting of a series of devices that are linked together via a domino effect – whereby one component triggers the next in the sequence.
The idea was originally inspired by the American cartoonist of the same name who often depicted such contraptions in his drawings.
YouTube has since become a haven for wacky inventors to show off their Rube Goldberg machines. Our current favourite is an incredible one-shot video posted by user Kaplamino.
His mesmerising Rube Goldberg machine is made up of everyday items - including bits of wood, coins, fidget spinners and pencils - all tied together by the movements of a blue marble. The end result has to be seen to be believed.
Kaplamino says that the contraption took him "three months of work and probably more than 500 fails" but was his "best video ever".
"Because everything is in a tilted plane, the hard part was to find different ways of having the marble riding up along the table (magnets, falling weight, catapult ...)," he said. "To do that, the marble has to be light. And because everything has to be triggered by this little marble, all the tricks are very unstable. Most fails happened when an element fall down earlier than expected.
"I learned a lot about chain reaction, and I discovered the amazing power of the hot glue gun."